Effect of lubrication mode and compaction temperature on the properties of Fe-Ni-Cu-Mo-C

Improved sintered properties are sought in new powder metallurgy parts applications and this need translates into increased green density. Several techniques have been evaluated for increased green density and, hence, higher sintered properties, including warm compaction and the elimination of internal lubricants. However, no study has examined these techniques using a non-bias test matrix. This study included two compaction temperatures and three lubrication techniques applied to a Fe-2Ni-2Cu-0.85Mo-0.8C alloy using a PTFE lubricant. All test conditions were evaluated in terms of green and sintered properties, including ejection force, green and sintered density, tensile strength, and impact toughness. In the context of the experimental matrix evaluated, dry lubricant admixing and cold compaction promoted the best combination of green and sintered properties compared to powder coating, die wall lubrication, and warm compaction.